|Articles|July 2, 2021

Johnson & Johnson Vaccine Shows Strong, Persistent Activity Against Delta Variant

Author(s)Killian Meara

The activity was higher than what was recently observed for the South African variant.

On Thursday, Johnson & Johnson announced new data that shows their COVID-19 vaccine generates strong, persistent activity against the Delta COVID-19 variant and other highly prevalent strains of the SARS-CoV-2 virus.

Additionally, the data showed that the durability of the immune response lasted through at least eight months.

The data from the two preprint study summaries were published on bioRxiv.

The single-shot, adenovirus vaccine was developed by Janssen Pharmaceuticals, an innovative medical research & pharmaceutical product development company owned by Johnson & Johnson.

“Current data for the eight months studied so far show that the single-shot Johnson & Johnson COVID-19 vaccine generates a strong neutralizing antibody response that does not wane; rather, we observe an improvement over time. In addition, we observe a persistent and particularly robust, durable cellular immune response,” Mathai Mammen, global head of Janssen research & development said. “With each new dataset, we build on our solid foundation of evidence that our single-shot COVID-19 vaccine plays a critical role in ending the pandemic, which continues to evolve and pose new challenges to global health.”

The preprint data discusses a new analysis of blood samples from a subset of participants in the Phase 3 ENSEMBLE study. The data demonstrated that the vaccine elicited neutralizing antibody activity against the Delta variant.

The study also showed that the vaccine generated humoral and cellular immune responses which lasted through at least eight months, the latest timepoint recorded in the study.

“Today’s newly announced studies reinforce the ability of the Johnson & Johnson COVID-19 vaccine to help protect the health of people globally,” Paul Stoffels, vice chairman of the executive committee and chief scientific officer at Johnson & Johnson said. “We believe that our vaccine offers durable protection against COVID-19 and elicits neutralizing activity against the Delta variant. This adds to the robust body of clinical data supporting our single-shot vaccine’s ability to protect against multiple variants of concern.”


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